OpenEuphoria

Re: Euphoria and Windows XP SP2

• Posted by Robert Craig <rds at RapidEuphoria.com> Sep 18, 2004
• 433 views

Tommy Carlier wrote:
> In SP2, DEP is by default enabled only for critical
> services and applications. This causes no problems with
> Euphoria. However, when I enable it for ALL applications,
> Euphoria-programs get machine errors. Like suggested in
> previous posts, the manually constructed assembly-routines
> cause problems. But there were also problems with c_func
> and c_proc: I can show a message_box from Euphoria, but
> I can't open a window (CreateWindow and CreateWindowEx
> throw an error). This even happens with the small demos
> that come with Euphoria (WINDOW.EXW, WINWIRE.EXW).

Internally, for Windows call-backs, Euphoria allocates
data segment space and copies executable code into it. 
This lets me provide an "infinite" number of call-back routines,
with numbers of arguments from 0 to 9.
In practice, no Win32Lib-based program that I've tried
uses more than about 20 unique call-back routines, 
most taking 4 arguments. If there were fixed limits on the 
number of call-back routines with a given number of 
arguments, I could avoid using the data segment to store code.

In the new open source version of Euphoria written 100% in Euphoria,
I've taken the approach of having a fixed number (20) of 
call-back routines, and it runs every Windows program I throw at it
(including Judith's IDE). I could support "infinite" call-backs 
there too, but it's extra work, and people want me to hurry up 
(If 20 isn't enough, just edit the interpreter to make it 30, 40 ...)

I have no idea how many people are going to fully enable DEP.
I imagine there are other important apps that will die 
if it's turned on.

Regards,
   Rob Craig
   Rapid Deployment Software
   http://www.RapidEuphoria.com